Brain-derived neurotrophic factor (BDNF) Val(66)Met polymorphism differentially predicts hippocampal function in...

Area of Science:

• Neuroscience
• Genetics
• Psychiatry

Background:

• The brain-derived neurotrophic factor (BDNF) Val(66)Met single-nucleotide polymorphism (SNP) affects neuronal function and memory.
• Hippocampal dysfunction is implicated in schizophrenia, and genetic factors related to BDNF may play a role.

Purpose of the Study:

• To directly investigate the relationship between the BDNF Val(66)Met SNP and hippocampal function in schizophrenia patients.
• To examine how this genetic variation influences brain activity during rest and working memory tasks.

Main Methods:

• Genotyping for the BDNF Val(66)Met SNP in 47 medication-free schizophrenia patients and 74 healthy controls.
• [(15)O]H(2)O Positron Emission Tomography (PET) to measure hippocampal regional cerebral blood flow (rCBF) at rest and during a working memory task.

Main Results:

• Schizophrenia patients with the Met allele showed reduced hippocampal rCBF compared to controls, a diagnosis-by-genotype interaction.
• A significant diagnosis-by-genotype interaction was observed in hippocampal-prefrontal coupling during rest.
• Working memory-related hippocampal rCBF changes were attenuated in Met allele-carrying patients.

Conclusions:

• Hippocampal neurophysiology differs between schizophrenia patients and controls based on BDNF Val(66)Met genotype.
• These findings support the hypothesis that BDNF genetic variations contribute to hippocampal and frontotemporal dysfunction in schizophrenia.
• Further research is needed to explore patient-specific factors influencing these genetic interactions.